| /* Intel 386 target-dependent stuff. |
| Copyright 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, |
| 1998, 1999, 2000, 2001 |
| Free Software Foundation, Inc. |
| |
| This file is part of GDB. |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program; if not, write to the Free Software |
| Foundation, Inc., 59 Temple Place - Suite 330, |
| Boston, MA 02111-1307, USA. */ |
| |
| #include "defs.h" |
| #include "gdb_string.h" |
| #include "frame.h" |
| #include "inferior.h" |
| #include "gdbcore.h" |
| #include "target.h" |
| #include "floatformat.h" |
| #include "symtab.h" |
| #include "gdbcmd.h" |
| #include "command.h" |
| #include "arch-utils.h" |
| #include "regcache.h" |
| #include "doublest.h" |
| #include "value.h" |
| #include "gdb_assert.h" |
| |
| #include "elf-bfd.h" |
| |
| #include "i386-tdep.h" |
| |
| #undef XMALLOC |
| #define XMALLOC(TYPE) ((TYPE*) xmalloc (sizeof (TYPE))) |
| |
| /* Names of the registers. The first 10 registers match the register |
| numbering scheme used by GCC for stabs and DWARF. */ |
| static char *i386_register_names[] = |
| { |
| "eax", "ecx", "edx", "ebx", |
| "esp", "ebp", "esi", "edi", |
| "eip", "eflags", "cs", "ss", |
| "ds", "es", "fs", "gs", |
| "st0", "st1", "st2", "st3", |
| "st4", "st5", "st6", "st7", |
| "fctrl", "fstat", "ftag", "fiseg", |
| "fioff", "foseg", "fooff", "fop", |
| "xmm0", "xmm1", "xmm2", "xmm3", |
| "xmm4", "xmm5", "xmm6", "xmm7", |
| "mxcsr" |
| }; |
| |
| /* i386_register_offset[i] is the offset into the register file of the |
| start of register number i. We initialize this from |
| i386_register_size. */ |
| static int i386_register_offset[MAX_NUM_REGS]; |
| |
| /* i386_register_size[i] is the number of bytes of storage in GDB's |
| register array occupied by register i. */ |
| static int i386_register_size[MAX_NUM_REGS] = { |
| 4, 4, 4, 4, |
| 4, 4, 4, 4, |
| 4, 4, 4, 4, |
| 4, 4, 4, 4, |
| 10, 10, 10, 10, |
| 10, 10, 10, 10, |
| 4, 4, 4, 4, |
| 4, 4, 4, 4, |
| 16, 16, 16, 16, |
| 16, 16, 16, 16, |
| 4 |
| }; |
| |
| /* Return the name of register REG. */ |
| |
| char * |
| i386_register_name (int reg) |
| { |
| if (reg < 0) |
| return NULL; |
| if (reg >= sizeof (i386_register_names) / sizeof (*i386_register_names)) |
| return NULL; |
| |
| return i386_register_names[reg]; |
| } |
| |
| /* Return the offset into the register array of the start of register |
| number REG. */ |
| int |
| i386_register_byte (int reg) |
| { |
| return i386_register_offset[reg]; |
| } |
| |
| /* Return the number of bytes of storage in GDB's register array |
| occupied by register REG. */ |
| |
| int |
| i386_register_raw_size (int reg) |
| { |
| return i386_register_size[reg]; |
| } |
| |
| /* Return the size in bytes of the virtual type of register REG. */ |
| |
| int |
| i386_register_virtual_size (int reg) |
| { |
| return TYPE_LENGTH (REGISTER_VIRTUAL_TYPE (reg)); |
| } |
| |
| /* Convert stabs register number REG to the appropriate register |
| number used by GDB. */ |
| |
| int |
| i386_stab_reg_to_regnum (int reg) |
| { |
| /* This implements what GCC calls the "default" register map. */ |
| if (reg >= 0 && reg <= 7) |
| { |
| /* General registers. */ |
| return reg; |
| } |
| else if (reg >= 12 && reg <= 19) |
| { |
| /* Floating-point registers. */ |
| return reg - 12 + FP0_REGNUM; |
| } |
| else if (reg >= 21 && reg <= 28) |
| { |
| /* SSE registers. */ |
| return reg - 21 + XMM0_REGNUM; |
| } |
| else if (reg >= 29 && reg <= 36) |
| { |
| /* MMX registers. */ |
| /* FIXME: kettenis/2001-07-28: Should we have the MMX registers |
| as pseudo-registers? */ |
| return reg - 29 + FP0_REGNUM; |
| } |
| |
| /* This will hopefully provoke a warning. */ |
| return NUM_REGS + NUM_PSEUDO_REGS; |
| } |
| |
| /* Convert Dwarf register number REG to the appropriate register |
| number used by GDB. */ |
| |
| int |
| i386_dwarf_reg_to_regnum (int reg) |
| { |
| /* The DWARF register numbering includes %eip and %eflags, and |
| numbers the floating point registers differently. */ |
| if (reg >= 0 && reg <= 9) |
| { |
| /* General registers. */ |
| return reg; |
| } |
| else if (reg >= 11 && reg <= 18) |
| { |
| /* Floating-point registers. */ |
| return reg - 11 + FP0_REGNUM; |
| } |
| else if (reg >= 21) |
| { |
| /* The SSE and MMX registers have identical numbers as in stabs. */ |
| return i386_stab_reg_to_regnum (reg); |
| } |
| |
| /* This will hopefully provoke a warning. */ |
| return NUM_REGS + NUM_PSEUDO_REGS; |
| } |
| |
| |
| /* This is the variable that is set with "set disassembly-flavor", and |
| its legitimate values. */ |
| static const char att_flavor[] = "att"; |
| static const char intel_flavor[] = "intel"; |
| static const char *valid_flavors[] = |
| { |
| att_flavor, |
| intel_flavor, |
| NULL |
| }; |
| static const char *disassembly_flavor = att_flavor; |
| |
| /* Stdio style buffering was used to minimize calls to ptrace, but |
| this buffering did not take into account that the code section |
| being accessed may not be an even number of buffers long (even if |
| the buffer is only sizeof(int) long). In cases where the code |
| section size happened to be a non-integral number of buffers long, |
| attempting to read the last buffer would fail. Simply using |
| target_read_memory and ignoring errors, rather than read_memory, is |
| not the correct solution, since legitimate access errors would then |
| be totally ignored. To properly handle this situation and continue |
| to use buffering would require that this code be able to determine |
| the minimum code section size granularity (not the alignment of the |
| section itself, since the actual failing case that pointed out this |
| problem had a section alignment of 4 but was not a multiple of 4 |
| bytes long), on a target by target basis, and then adjust it's |
| buffer size accordingly. This is messy, but potentially feasible. |
| It probably needs the bfd library's help and support. For now, the |
| buffer size is set to 1. (FIXME -fnf) */ |
| |
| #define CODESTREAM_BUFSIZ 1 /* Was sizeof(int), see note above. */ |
| static CORE_ADDR codestream_next_addr; |
| static CORE_ADDR codestream_addr; |
| static unsigned char codestream_buf[CODESTREAM_BUFSIZ]; |
| static int codestream_off; |
| static int codestream_cnt; |
| |
| #define codestream_tell() (codestream_addr + codestream_off) |
| #define codestream_peek() \ |
| (codestream_cnt == 0 ? \ |
| codestream_fill(1) : codestream_buf[codestream_off]) |
| #define codestream_get() \ |
| (codestream_cnt-- == 0 ? \ |
| codestream_fill(0) : codestream_buf[codestream_off++]) |
| |
| static unsigned char |
| codestream_fill (int peek_flag) |
| { |
| codestream_addr = codestream_next_addr; |
| codestream_next_addr += CODESTREAM_BUFSIZ; |
| codestream_off = 0; |
| codestream_cnt = CODESTREAM_BUFSIZ; |
| read_memory (codestream_addr, (char *) codestream_buf, CODESTREAM_BUFSIZ); |
| |
| if (peek_flag) |
| return (codestream_peek ()); |
| else |
| return (codestream_get ()); |
| } |
| |
| static void |
| codestream_seek (CORE_ADDR place) |
| { |
| codestream_next_addr = place / CODESTREAM_BUFSIZ; |
| codestream_next_addr *= CODESTREAM_BUFSIZ; |
| codestream_cnt = 0; |
| codestream_fill (1); |
| while (codestream_tell () != place) |
| codestream_get (); |
| } |
| |
| static void |
| codestream_read (unsigned char *buf, int count) |
| { |
| unsigned char *p; |
| int i; |
| p = buf; |
| for (i = 0; i < count; i++) |
| *p++ = codestream_get (); |
| } |
| |
| |
| /* If the next instruction is a jump, move to its target. */ |
| |
| static void |
| i386_follow_jump (void) |
| { |
| unsigned char buf[4]; |
| long delta; |
| |
| int data16; |
| CORE_ADDR pos; |
| |
| pos = codestream_tell (); |
| |
| data16 = 0; |
| if (codestream_peek () == 0x66) |
| { |
| codestream_get (); |
| data16 = 1; |
| } |
| |
| switch (codestream_get ()) |
| { |
| case 0xe9: |
| /* Relative jump: if data16 == 0, disp32, else disp16. */ |
| if (data16) |
| { |
| codestream_read (buf, 2); |
| delta = extract_signed_integer (buf, 2); |
| |
| /* Include the size of the jmp instruction (including the |
| 0x66 prefix). */ |
| pos += delta + 4; |
| } |
| else |
| { |
| codestream_read (buf, 4); |
| delta = extract_signed_integer (buf, 4); |
| |
| pos += delta + 5; |
| } |
| break; |
| case 0xeb: |
| /* Relative jump, disp8 (ignore data16). */ |
| codestream_read (buf, 1); |
| /* Sign-extend it. */ |
| delta = extract_signed_integer (buf, 1); |
| |
| pos += delta + 2; |
| break; |
| } |
| codestream_seek (pos); |
| } |
| |
| /* Find & return the amount a local space allocated, and advance the |
| codestream to the first register push (if any). |
| |
| If the entry sequence doesn't make sense, return -1, and leave |
| codestream pointer at a random spot. */ |
| |
| static long |
| i386_get_frame_setup (CORE_ADDR pc) |
| { |
| unsigned char op; |
| |
| codestream_seek (pc); |
| |
| i386_follow_jump (); |
| |
| op = codestream_get (); |
| |
| if (op == 0x58) /* popl %eax */ |
| { |
| /* This function must start with |
| |
| popl %eax 0x58 |
| xchgl %eax, (%esp) 0x87 0x04 0x24 |
| or xchgl %eax, 0(%esp) 0x87 0x44 0x24 0x00 |
| |
| (the System V compiler puts out the second `xchg' |
| instruction, and the assembler doesn't try to optimize it, so |
| the 'sib' form gets generated). This sequence is used to get |
| the address of the return buffer for a function that returns |
| a structure. */ |
| int pos; |
| unsigned char buf[4]; |
| static unsigned char proto1[3] = { 0x87, 0x04, 0x24 }; |
| static unsigned char proto2[4] = { 0x87, 0x44, 0x24, 0x00 }; |
| |
| pos = codestream_tell (); |
| codestream_read (buf, 4); |
| if (memcmp (buf, proto1, 3) == 0) |
| pos += 3; |
| else if (memcmp (buf, proto2, 4) == 0) |
| pos += 4; |
| |
| codestream_seek (pos); |
| op = codestream_get (); /* Update next opcode. */ |
| } |
| |
| if (op == 0x68 || op == 0x6a) |
| { |
| /* This function may start with |
| |
| pushl constant |
| call _probe |
| addl $4, %esp |
| |
| followed by |
| |
| pushl %ebp |
| |
| etc. */ |
| int pos; |
| unsigned char buf[8]; |
| |
| /* Skip past the `pushl' instruction; it has either a one-byte |
| or a four-byte operand, depending on the opcode. */ |
| pos = codestream_tell (); |
| if (op == 0x68) |
| pos += 4; |
| else |
| pos += 1; |
| codestream_seek (pos); |
| |
| /* Read the following 8 bytes, which should be "call _probe" (6 |
| bytes) followed by "addl $4,%esp" (2 bytes). */ |
| codestream_read (buf, sizeof (buf)); |
| if (buf[0] == 0xe8 && buf[6] == 0xc4 && buf[7] == 0x4) |
| pos += sizeof (buf); |
| codestream_seek (pos); |
| op = codestream_get (); /* Update next opcode. */ |
| } |
| |
| if (op == 0x55) /* pushl %ebp */ |
| { |
| /* Check for "movl %esp, %ebp" -- can be written in two ways. */ |
| switch (codestream_get ()) |
| { |
| case 0x8b: |
| if (codestream_get () != 0xec) |
| return -1; |
| break; |
| case 0x89: |
| if (codestream_get () != 0xe5) |
| return -1; |
| break; |
| default: |
| return -1; |
| } |
| /* Check for stack adjustment |
| |
| subl $XXX, %esp |
| |
| NOTE: You can't subtract a 16 bit immediate from a 32 bit |
| reg, so we don't have to worry about a data16 prefix. */ |
| op = codestream_peek (); |
| if (op == 0x83) |
| { |
| /* `subl' with 8 bit immediate. */ |
| codestream_get (); |
| if (codestream_get () != 0xec) |
| /* Some instruction starting with 0x83 other than `subl'. */ |
| { |
| codestream_seek (codestream_tell () - 2); |
| return 0; |
| } |
| /* `subl' with signed byte immediate (though it wouldn't |
| make sense to be negative). */ |
| return (codestream_get ()); |
| } |
| else if (op == 0x81) |
| { |
| char buf[4]; |
| /* Maybe it is `subl' with a 32 bit immedediate. */ |
| codestream_get (); |
| if (codestream_get () != 0xec) |
| /* Some instruction starting with 0x81 other than `subl'. */ |
| { |
| codestream_seek (codestream_tell () - 2); |
| return 0; |
| } |
| /* It is `subl' with a 32 bit immediate. */ |
| codestream_read ((unsigned char *) buf, 4); |
| return extract_signed_integer (buf, 4); |
| } |
| else |
| { |
| return 0; |
| } |
| } |
| else if (op == 0xc8) |
| { |
| char buf[2]; |
| /* `enter' with 16 bit unsigned immediate. */ |
| codestream_read ((unsigned char *) buf, 2); |
| codestream_get (); /* Flush final byte of enter instruction. */ |
| return extract_unsigned_integer (buf, 2); |
| } |
| return (-1); |
| } |
| |
| /* Return the chain-pointer for FRAME. In the case of the i386, the |
| frame's nominal address is the address of a 4-byte word containing |
| the calling frame's address. */ |
| |
| CORE_ADDR |
| i386_frame_chain (struct frame_info *frame) |
| { |
| if (frame->signal_handler_caller) |
| return frame->frame; |
| |
| if (! inside_entry_file (frame->pc)) |
| return read_memory_unsigned_integer (frame->frame, 4); |
| |
| return 0; |
| } |
| |
| /* Determine whether the function invocation represented by FRAME does |
| not have a from on the stack associated with it. If it does not, |
| return non-zero, otherwise return zero. */ |
| |
| int |
| i386_frameless_function_invocation (struct frame_info *frame) |
| { |
| if (frame->signal_handler_caller) |
| return 0; |
| |
| return frameless_look_for_prologue (frame); |
| } |
| |
| /* Return the saved program counter for FRAME. */ |
| |
| CORE_ADDR |
| i386_frame_saved_pc (struct frame_info *frame) |
| { |
| /* FIXME: kettenis/2001-05-09: Conditionalizing the next bit of code |
| on SIGCONTEXT_PC_OFFSET and I386V4_SIGTRAMP_SAVED_PC should be |
| considered a temporary hack. I plan to come up with something |
| better when we go multi-arch. */ |
| #if defined (SIGCONTEXT_PC_OFFSET) || defined (I386V4_SIGTRAMP_SAVED_PC) |
| if (frame->signal_handler_caller) |
| return sigtramp_saved_pc (frame); |
| #endif |
| |
| return read_memory_unsigned_integer (frame->frame + 4, 4); |
| } |
| |
| CORE_ADDR |
| i386go32_frame_saved_pc (struct frame_info *frame) |
| { |
| return read_memory_integer (frame->frame + 4, 4); |
| } |
| |
| /* Immediately after a function call, return the saved pc. */ |
| |
| CORE_ADDR |
| i386_saved_pc_after_call (struct frame_info *frame) |
| { |
| return read_memory_unsigned_integer (read_register (SP_REGNUM), 4); |
| } |
| |
| /* Return number of args passed to a frame. |
| Can return -1, meaning no way to tell. */ |
| |
| int |
| i386_frame_num_args (struct frame_info *fi) |
| { |
| #if 1 |
| return -1; |
| #else |
| /* This loses because not only might the compiler not be popping the |
| args right after the function call, it might be popping args from |
| both this call and a previous one, and we would say there are |
| more args than there really are. */ |
| |
| int retpc; |
| unsigned char op; |
| struct frame_info *pfi; |
| |
| /* On the i386, the instruction following the call could be: |
| popl %ecx - one arg |
| addl $imm, %esp - imm/4 args; imm may be 8 or 32 bits |
| anything else - zero args. */ |
| |
| int frameless; |
| |
| frameless = FRAMELESS_FUNCTION_INVOCATION (fi); |
| if (frameless) |
| /* In the absence of a frame pointer, GDB doesn't get correct |
| values for nameless arguments. Return -1, so it doesn't print |
| any nameless arguments. */ |
| return -1; |
| |
| pfi = get_prev_frame (fi); |
| if (pfi == 0) |
| { |
| /* NOTE: This can happen if we are looking at the frame for |
| main, because FRAME_CHAIN_VALID won't let us go into start. |
| If we have debugging symbols, that's not really a big deal; |
| it just means it will only show as many arguments to main as |
| are declared. */ |
| return -1; |
| } |
| else |
| { |
| retpc = pfi->pc; |
| op = read_memory_integer (retpc, 1); |
| if (op == 0x59) /* pop %ecx */ |
| return 1; |
| else if (op == 0x83) |
| { |
| op = read_memory_integer (retpc + 1, 1); |
| if (op == 0xc4) |
| /* addl $<signed imm 8 bits>, %esp */ |
| return (read_memory_integer (retpc + 2, 1) & 0xff) / 4; |
| else |
| return 0; |
| } |
| else if (op == 0x81) /* `add' with 32 bit immediate. */ |
| { |
| op = read_memory_integer (retpc + 1, 1); |
| if (op == 0xc4) |
| /* addl $<imm 32>, %esp */ |
| return read_memory_integer (retpc + 2, 4) / 4; |
| else |
| return 0; |
| } |
| else |
| { |
| return 0; |
| } |
| } |
| #endif |
| } |
| |
| /* Parse the first few instructions the function to see what registers |
| were stored. |
| |
| We handle these cases: |
| |
| The startup sequence can be at the start of the function, or the |
| function can start with a branch to startup code at the end. |
| |
| %ebp can be set up with either the 'enter' instruction, or "pushl |
| %ebp, movl %esp, %ebp" (`enter' is too slow to be useful, but was |
| once used in the System V compiler). |
| |
| Local space is allocated just below the saved %ebp by either the |
| 'enter' instruction, or by "subl $<size>, %esp". 'enter' has a 16 |
| bit unsigned argument for space to allocate, and the 'addl' |
| instruction could have either a signed byte, or 32 bit immediate. |
| |
| Next, the registers used by this function are pushed. With the |
| System V compiler they will always be in the order: %edi, %esi, |
| %ebx (and sometimes a harmless bug causes it to also save but not |
| restore %eax); however, the code below is willing to see the pushes |
| in any order, and will handle up to 8 of them. |
| |
| If the setup sequence is at the end of the function, then the next |
| instruction will be a branch back to the start. */ |
| |
| void |
| i386_frame_init_saved_regs (struct frame_info *fip) |
| { |
| long locals = -1; |
| unsigned char op; |
| CORE_ADDR dummy_bottom; |
| CORE_ADDR addr; |
| CORE_ADDR pc; |
| int i; |
| |
| if (fip->saved_regs) |
| return; |
| |
| frame_saved_regs_zalloc (fip); |
| |
| /* If the frame is the end of a dummy, compute where the beginning |
| would be. */ |
| dummy_bottom = fip->frame - 4 - REGISTER_BYTES - CALL_DUMMY_LENGTH; |
| |
| /* Check if the PC points in the stack, in a dummy frame. */ |
| if (dummy_bottom <= fip->pc && fip->pc <= fip->frame) |
| { |
| /* All registers were saved by push_call_dummy. */ |
| addr = fip->frame; |
| for (i = 0; i < NUM_REGS; i++) |
| { |
| addr -= REGISTER_RAW_SIZE (i); |
| fip->saved_regs[i] = addr; |
| } |
| return; |
| } |
| |
| pc = get_pc_function_start (fip->pc); |
| if (pc != 0) |
| locals = i386_get_frame_setup (pc); |
| |
| if (locals >= 0) |
| { |
| addr = fip->frame - 4 - locals; |
| for (i = 0; i < 8; i++) |
| { |
| op = codestream_get (); |
| if (op < 0x50 || op > 0x57) |
| break; |
| #ifdef I386_REGNO_TO_SYMMETRY |
| /* Dynix uses different internal numbering. Ick. */ |
| fip->saved_regs[I386_REGNO_TO_SYMMETRY (op - 0x50)] = addr; |
| #else |
| fip->saved_regs[op - 0x50] = addr; |
| #endif |
| addr -= 4; |
| } |
| } |
| |
| fip->saved_regs[PC_REGNUM] = fip->frame + 4; |
| fip->saved_regs[FP_REGNUM] = fip->frame; |
| } |
| |
| /* Return PC of first real instruction. */ |
| |
| int |
| i386_skip_prologue (int pc) |
| { |
| unsigned char op; |
| int i; |
| static unsigned char pic_pat[6] = |
| { 0xe8, 0, 0, 0, 0, /* call 0x0 */ |
| 0x5b, /* popl %ebx */ |
| }; |
| CORE_ADDR pos; |
| |
| if (i386_get_frame_setup (pc) < 0) |
| return (pc); |
| |
| /* Found valid frame setup -- codestream now points to start of push |
| instructions for saving registers. */ |
| |
| /* Skip over register saves. */ |
| for (i = 0; i < 8; i++) |
| { |
| op = codestream_peek (); |
| /* Break if not `pushl' instrunction. */ |
| if (op < 0x50 || op > 0x57) |
| break; |
| codestream_get (); |
| } |
| |
| /* The native cc on SVR4 in -K PIC mode inserts the following code |
| to get the address of the global offset table (GOT) into register |
| %ebx |
| |
| call 0x0 |
| popl %ebx |
| movl %ebx,x(%ebp) (optional) |
| addl y,%ebx |
| |
| This code is with the rest of the prologue (at the end of the |
| function), so we have to skip it to get to the first real |
| instruction at the start of the function. */ |
| |
| pos = codestream_tell (); |
| for (i = 0; i < 6; i++) |
| { |
| op = codestream_get (); |
| if (pic_pat[i] != op) |
| break; |
| } |
| if (i == 6) |
| { |
| unsigned char buf[4]; |
| long delta = 6; |
| |
| op = codestream_get (); |
| if (op == 0x89) /* movl %ebx, x(%ebp) */ |
| { |
| op = codestream_get (); |
| if (op == 0x5d) /* One byte offset from %ebp. */ |
| { |
| delta += 3; |
| codestream_read (buf, 1); |
| } |
| else if (op == 0x9d) /* Four byte offset from %ebp. */ |
| { |
| delta += 6; |
| codestream_read (buf, 4); |
| } |
| else /* Unexpected instruction. */ |
| delta = -1; |
| op = codestream_get (); |
| } |
| /* addl y,%ebx */ |
| if (delta > 0 && op == 0x81 && codestream_get () == 0xc3) |
| { |
| pos += delta + 6; |
| } |
| } |
| codestream_seek (pos); |
| |
| i386_follow_jump (); |
| |
| return (codestream_tell ()); |
| } |
| |
| void |
| i386_push_dummy_frame (void) |
| { |
| CORE_ADDR sp = read_register (SP_REGNUM); |
| CORE_ADDR fp; |
| int regnum; |
| char regbuf[MAX_REGISTER_RAW_SIZE]; |
| |
| sp = push_word (sp, read_register (PC_REGNUM)); |
| sp = push_word (sp, read_register (FP_REGNUM)); |
| fp = sp; |
| for (regnum = 0; regnum < NUM_REGS; regnum++) |
| { |
| read_register_gen (regnum, regbuf); |
| sp = push_bytes (sp, regbuf, REGISTER_RAW_SIZE (regnum)); |
| } |
| write_register (SP_REGNUM, sp); |
| write_register (FP_REGNUM, fp); |
| } |
| |
| /* Insert the (relative) function address into the call sequence |
| stored at DYMMY. */ |
| |
| void |
| i386_fix_call_dummy (char *dummy, CORE_ADDR pc, CORE_ADDR fun, int nargs, |
| struct value **args, struct type *type, int gcc_p) |
| { |
| int from, to, delta, loc; |
| |
| loc = (int)(read_register (SP_REGNUM) - CALL_DUMMY_LENGTH); |
| from = loc + 5; |
| to = (int)(fun); |
| delta = to - from; |
| |
| *((char *)(dummy) + 1) = (delta & 0xff); |
| *((char *)(dummy) + 2) = ((delta >> 8) & 0xff); |
| *((char *)(dummy) + 3) = ((delta >> 16) & 0xff); |
| *((char *)(dummy) + 4) = ((delta >> 24) & 0xff); |
| } |
| |
| void |
| i386_pop_frame (void) |
| { |
| struct frame_info *frame = get_current_frame (); |
| CORE_ADDR fp; |
| int regnum; |
| char regbuf[MAX_REGISTER_RAW_SIZE]; |
| |
| fp = FRAME_FP (frame); |
| i386_frame_init_saved_regs (frame); |
| |
| for (regnum = 0; regnum < NUM_REGS; regnum++) |
| { |
| CORE_ADDR addr; |
| addr = frame->saved_regs[regnum]; |
| if (addr) |
| { |
| read_memory (addr, regbuf, REGISTER_RAW_SIZE (regnum)); |
| write_register_bytes (REGISTER_BYTE (regnum), regbuf, |
| REGISTER_RAW_SIZE (regnum)); |
| } |
| } |
| write_register (FP_REGNUM, read_memory_integer (fp, 4)); |
| write_register (PC_REGNUM, read_memory_integer (fp + 4, 4)); |
| write_register (SP_REGNUM, fp + 8); |
| flush_cached_frames (); |
| } |
| |
| |
| #ifdef GET_LONGJMP_TARGET |
| |
| /* FIXME: Multi-arching does not set JB_PC and JB_ELEMENT_SIZE yet. |
| Fill in with dummy value to enable compilation. */ |
| #ifndef JB_PC |
| #define JB_PC 0 |
| #endif /* JB_PC */ |
| |
| #ifndef JB_ELEMENT_SIZE |
| #define JB_ELEMENT_SIZE 4 |
| #endif /* JB_ELEMENT_SIZE */ |
| |
| /* Figure out where the longjmp will land. Slurp the args out of the |
| stack. We expect the first arg to be a pointer to the jmp_buf |
| structure from which we extract the pc (JB_PC) that we will land |
| at. The pc is copied into PC. This routine returns true on |
| success. */ |
| |
| int |
| get_longjmp_target (CORE_ADDR *pc) |
| { |
| char buf[TARGET_PTR_BIT / TARGET_CHAR_BIT]; |
| CORE_ADDR sp, jb_addr; |
| |
| sp = read_register (SP_REGNUM); |
| |
| if (target_read_memory (sp + SP_ARG0, /* Offset of first arg on stack. */ |
| buf, |
| TARGET_PTR_BIT / TARGET_CHAR_BIT)) |
| return 0; |
| |
| jb_addr = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT); |
| |
| if (target_read_memory (jb_addr + JB_PC * JB_ELEMENT_SIZE, buf, |
| TARGET_PTR_BIT / TARGET_CHAR_BIT)) |
| return 0; |
| |
| *pc = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT); |
| |
| return 1; |
| } |
| |
| #endif /* GET_LONGJMP_TARGET */ |
| |
| |
| CORE_ADDR |
| i386_push_arguments (int nargs, struct value **args, CORE_ADDR sp, |
| int struct_return, CORE_ADDR struct_addr) |
| { |
| sp = default_push_arguments (nargs, args, sp, struct_return, struct_addr); |
| |
| if (struct_return) |
| { |
| char buf[4]; |
| |
| sp -= 4; |
| store_address (buf, 4, struct_addr); |
| write_memory (sp, buf, 4); |
| } |
| |
| return sp; |
| } |
| |
| void |
| i386_store_struct_return (CORE_ADDR addr, CORE_ADDR sp) |
| { |
| /* Do nothing. Everything was already done by i386_push_arguments. */ |
| } |
| |
| /* These registers are used for returning integers (and on some |
| targets also for returning `struct' and `union' values when their |
| size and alignment match an integer type). */ |
| #define LOW_RETURN_REGNUM 0 /* %eax */ |
| #define HIGH_RETURN_REGNUM 2 /* %edx */ |
| |
| /* Extract from an array REGBUF containing the (raw) register state, a |
| function return value of TYPE, and copy that, in virtual format, |
| into VALBUF. */ |
| |
| void |
| i386_extract_return_value (struct type *type, char *regbuf, char *valbuf) |
| { |
| int len = TYPE_LENGTH (type); |
| |
| if (TYPE_CODE (type) == TYPE_CODE_STRUCT |
| && TYPE_NFIELDS (type) == 1) |
| { |
| i386_extract_return_value (TYPE_FIELD_TYPE (type, 0), regbuf, valbuf); |
| return; |
| } |
| |
| if (TYPE_CODE (type) == TYPE_CODE_FLT) |
| { |
| if (NUM_FREGS == 0) |
| { |
| warning ("Cannot find floating-point return value."); |
| memset (valbuf, 0, len); |
| return; |
| } |
| |
| /* Floating-point return values can be found in %st(0). Convert |
| its contents to the desired type. This is probably not |
| exactly how it would happen on the target itself, but it is |
| the best we can do. */ |
| convert_typed_floating (®buf[REGISTER_BYTE (FP0_REGNUM)], |
| builtin_type_i387_ext, valbuf, type); |
| } |
| else |
| { |
| int low_size = REGISTER_RAW_SIZE (LOW_RETURN_REGNUM); |
| int high_size = REGISTER_RAW_SIZE (HIGH_RETURN_REGNUM); |
| |
| if (len <= low_size) |
| memcpy (valbuf, ®buf[REGISTER_BYTE (LOW_RETURN_REGNUM)], len); |
| else if (len <= (low_size + high_size)) |
| { |
| memcpy (valbuf, |
| ®buf[REGISTER_BYTE (LOW_RETURN_REGNUM)], low_size); |
| memcpy (valbuf + low_size, |
| ®buf[REGISTER_BYTE (HIGH_RETURN_REGNUM)], len - low_size); |
| } |
| else |
| internal_error (__FILE__, __LINE__, |
| "Cannot extract return value of %d bytes long.", len); |
| } |
| } |
| |
| /* Write into the appropriate registers a function return value stored |
| in VALBUF of type TYPE, given in virtual format. */ |
| |
| void |
| i386_store_return_value (struct type *type, char *valbuf) |
| { |
| int len = TYPE_LENGTH (type); |
| |
| if (TYPE_CODE (type) == TYPE_CODE_STRUCT |
| && TYPE_NFIELDS (type) == 1) |
| { |
| i386_store_return_value (TYPE_FIELD_TYPE (type, 0), valbuf); |
| return; |
| } |
| |
| if (TYPE_CODE (type) == TYPE_CODE_FLT) |
| { |
| unsigned int fstat; |
| char buf[FPU_REG_RAW_SIZE]; |
| |
| if (NUM_FREGS == 0) |
| { |
| warning ("Cannot set floating-point return value."); |
| return; |
| } |
| |
| /* Returning floating-point values is a bit tricky. Apart from |
| storing the return value in %st(0), we have to simulate the |
| state of the FPU at function return point. */ |
| |
| /* Convert the value found in VALBUF to the extended |
| floating-point format used by the FPU. This is probably |
| not exactly how it would happen on the target itself, but |
| it is the best we can do. */ |
| convert_typed_floating (valbuf, type, buf, builtin_type_i387_ext); |
| write_register_bytes (REGISTER_BYTE (FP0_REGNUM), buf, |
| FPU_REG_RAW_SIZE); |
| |
| /* Set the top of the floating-point register stack to 7. The |
| actual value doesn't really matter, but 7 is what a normal |
| function return would end up with if the program started out |
| with a freshly initialized FPU. */ |
| fstat = read_register (FSTAT_REGNUM); |
| fstat |= (7 << 11); |
| write_register (FSTAT_REGNUM, fstat); |
| |
| /* Mark %st(1) through %st(7) as empty. Since we set the top of |
| the floating-point register stack to 7, the appropriate value |
| for the tag word is 0x3fff. */ |
| write_register (FTAG_REGNUM, 0x3fff); |
| } |
| else |
| { |
| int low_size = REGISTER_RAW_SIZE (LOW_RETURN_REGNUM); |
| int high_size = REGISTER_RAW_SIZE (HIGH_RETURN_REGNUM); |
| |
| if (len <= low_size) |
| write_register_bytes (REGISTER_BYTE (LOW_RETURN_REGNUM), valbuf, len); |
| else if (len <= (low_size + high_size)) |
| { |
| write_register_bytes (REGISTER_BYTE (LOW_RETURN_REGNUM), |
| valbuf, low_size); |
| write_register_bytes (REGISTER_BYTE (HIGH_RETURN_REGNUM), |
| valbuf + low_size, len - low_size); |
| } |
| else |
| internal_error (__FILE__, __LINE__, |
| "Cannot store return value of %d bytes long.", len); |
| } |
| } |
| |
| /* Extract from an array REGBUF containing the (raw) register state |
| the address in which a function should return its structure value, |
| as a CORE_ADDR. */ |
| |
| CORE_ADDR |
| i386_extract_struct_value_address (char *regbuf) |
| { |
| return extract_address (®buf[REGISTER_BYTE (LOW_RETURN_REGNUM)], |
| REGISTER_RAW_SIZE (LOW_RETURN_REGNUM)); |
| } |
| |
| |
| /* Return the GDB type object for the "standard" data type of data in |
| register REGNUM. Perhaps %esi and %edi should go here, but |
| potentially they could be used for things other than address. */ |
| |
| struct type * |
| i386_register_virtual_type (int regnum) |
| { |
| if (regnum == PC_REGNUM || regnum == FP_REGNUM || regnum == SP_REGNUM) |
| return lookup_pointer_type (builtin_type_void); |
| |
| if (IS_FP_REGNUM (regnum)) |
| return builtin_type_i387_ext; |
| |
| if (IS_SSE_REGNUM (regnum)) |
| return builtin_type_v4sf; |
| |
| return builtin_type_int; |
| } |
| |
| /* Return true iff register REGNUM's virtual format is different from |
| its raw format. Note that this definition assumes that the host |
| supports IEEE 32-bit floats, since it doesn't say that SSE |
| registers need conversion. Even if we can't find a counterexample, |
| this is still sloppy. */ |
| |
| int |
| i386_register_convertible (int regnum) |
| { |
| return IS_FP_REGNUM (regnum); |
| } |
| |
| /* Convert data from raw format for register REGNUM in buffer FROM to |
| virtual format with type TYPE in buffer TO. */ |
| |
| void |
| i386_register_convert_to_virtual (int regnum, struct type *type, |
| char *from, char *to) |
| { |
| gdb_assert (IS_FP_REGNUM (regnum)); |
| |
| /* We only support floating-point values. */ |
| if (TYPE_CODE (type) != TYPE_CODE_FLT) |
| { |
| warning ("Cannot convert floating-point register value " |
| "to non-floating-point type."); |
| memset (to, 0, TYPE_LENGTH (type)); |
| return; |
| } |
| |
| /* Convert to TYPE. This should be a no-op if TYPE is equivalent to |
| the extended floating-point format used by the FPU. */ |
| convert_typed_floating (from, builtin_type_i387_ext, to, type); |
| } |
| |
| /* Convert data from virtual format with type TYPE in buffer FROM to |
| raw format for register REGNUM in buffer TO. */ |
| |
| void |
| i386_register_convert_to_raw (struct type *type, int regnum, |
| char *from, char *to) |
| { |
| gdb_assert (IS_FP_REGNUM (regnum)); |
| |
| /* We only support floating-point values. */ |
| if (TYPE_CODE (type) != TYPE_CODE_FLT) |
| { |
| warning ("Cannot convert non-floating-point type " |
| "to floating-point register value."); |
| memset (to, 0, TYPE_LENGTH (type)); |
| return; |
| } |
| |
| /* Convert from TYPE. This should be a no-op if TYPE is equivalent |
| to the extended floating-point format used by the FPU. */ |
| convert_typed_floating (from, type, to, builtin_type_i387_ext); |
| } |
| |
| |
| #ifdef I386V4_SIGTRAMP_SAVED_PC |
| /* Get saved user PC for sigtramp from the pushed ucontext on the |
| stack for all three variants of SVR4 sigtramps. */ |
| |
| CORE_ADDR |
| i386v4_sigtramp_saved_pc (struct frame_info *frame) |
| { |
| CORE_ADDR saved_pc_offset = 4; |
| char *name = NULL; |
| |
| find_pc_partial_function (frame->pc, &name, NULL, NULL); |
| if (name) |
| { |
| if (STREQ (name, "_sigreturn")) |
| saved_pc_offset = 132 + 14 * 4; |
| else if (STREQ (name, "_sigacthandler")) |
| saved_pc_offset = 80 + 14 * 4; |
| else if (STREQ (name, "sigvechandler")) |
| saved_pc_offset = 120 + 14 * 4; |
| } |
| |
| if (frame->next) |
| return read_memory_integer (frame->next->frame + saved_pc_offset, 4); |
| return read_memory_integer (read_register (SP_REGNUM) + saved_pc_offset, 4); |
| } |
| #endif /* I386V4_SIGTRAMP_SAVED_PC */ |
| |
| |
| #ifdef STATIC_TRANSFORM_NAME |
| /* SunPRO encodes the static variables. This is not related to C++ |
| mangling, it is done for C too. */ |
| |
| char * |
| sunpro_static_transform_name (char *name) |
| { |
| char *p; |
| if (IS_STATIC_TRANSFORM_NAME (name)) |
| { |
| /* For file-local statics there will be a period, a bunch of |
| junk (the contents of which match a string given in the |
| N_OPT), a period and the name. For function-local statics |
| there will be a bunch of junk (which seems to change the |
| second character from 'A' to 'B'), a period, the name of the |
| function, and the name. So just skip everything before the |
| last period. */ |
| p = strrchr (name, '.'); |
| if (p != NULL) |
| name = p + 1; |
| } |
| return name; |
| } |
| #endif /* STATIC_TRANSFORM_NAME */ |
| |
| |
| /* Stuff for WIN32 PE style DLL's but is pretty generic really. */ |
| |
| CORE_ADDR |
| skip_trampoline_code (CORE_ADDR pc, char *name) |
| { |
| if (pc && read_memory_unsigned_integer (pc, 2) == 0x25ff) /* jmp *(dest) */ |
| { |
| unsigned long indirect = read_memory_unsigned_integer (pc + 2, 4); |
| struct minimal_symbol *indsym = |
| indirect ? lookup_minimal_symbol_by_pc (indirect) : 0; |
| char *symname = indsym ? SYMBOL_NAME (indsym) : 0; |
| |
| if (symname) |
| { |
| if (strncmp (symname, "__imp_", 6) == 0 |
| || strncmp (symname, "_imp_", 5) == 0) |
| return name ? 1 : read_memory_unsigned_integer (indirect, 4); |
| } |
| } |
| return 0; /* Not a trampoline. */ |
| } |
| |
| |
| /* We have two flavours of disassembly. The machinery on this page |
| deals with switching between those. */ |
| |
| static int |
| gdb_print_insn_i386 (bfd_vma memaddr, disassemble_info *info) |
| { |
| if (disassembly_flavor == att_flavor) |
| return print_insn_i386_att (memaddr, info); |
| else if (disassembly_flavor == intel_flavor) |
| return print_insn_i386_intel (memaddr, info); |
| /* Never reached -- disassembly_flavour is always either att_flavor |
| or intel_flavor. */ |
| internal_error (__FILE__, __LINE__, "failed internal consistency check"); |
| } |
| |
| |
| static void |
| process_note_abi_tag_sections (bfd *abfd, asection *sect, void *obj) |
| { |
| int *os_ident_ptr = obj; |
| const char *name; |
| unsigned int sect_size; |
| |
| name = bfd_get_section_name (abfd, sect); |
| sect_size = bfd_section_size (abfd, sect); |
| if (strcmp (name, ".note.ABI-tag") == 0 && sect_size > 0) |
| { |
| unsigned int name_length, data_length, note_type; |
| char *note = alloca (sect_size); |
| |
| bfd_get_section_contents (abfd, sect, note, |
| (file_ptr) 0, (bfd_size_type) sect_size); |
| |
| name_length = bfd_h_get_32 (abfd, note); |
| data_length = bfd_h_get_32 (abfd, note + 4); |
| note_type = bfd_h_get_32 (abfd, note + 8); |
| |
| if (name_length == 4 && data_length == 16 && note_type == 1 |
| && strcmp (note + 12, "GNU") == 0) |
| { |
| int os_number = bfd_h_get_32 (abfd, note + 16); |
| |
| /* The case numbers are from abi-tags in glibc. */ |
| switch (os_number) |
| { |
| case 0: |
| *os_ident_ptr = ELFOSABI_LINUX; |
| break; |
| case 1: |
| *os_ident_ptr = ELFOSABI_HURD; |
| break; |
| case 2: |
| *os_ident_ptr = ELFOSABI_SOLARIS; |
| break; |
| default: |
| internal_error (__FILE__, __LINE__, |
| "process_note_abi_sections: " |
| "unknown OS number %d", os_number); |
| break; |
| } |
| } |
| } |
| } |
| |
| struct gdbarch * |
| i386_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches) |
| { |
| struct gdbarch_tdep *tdep; |
| struct gdbarch *gdbarch; |
| int os_ident; |
| |
| if (info.abfd != NULL |
| && bfd_get_flavour (info.abfd) == bfd_target_elf_flavour) |
| { |
| os_ident = elf_elfheader (info.abfd)->e_ident[EI_OSABI]; |
| |
| /* If os_ident is 0, it is not necessarily the case that we're |
| on a SYSV system. (ELFOSABI_NONE is defined to be 0.) |
| GNU/Linux uses a note section to record OS/ABI info, but |
| leaves e_ident[EI_OSABI] zero. So we have to check for note |
| sections too. */ |
| if (os_ident == ELFOSABI_NONE) |
| bfd_map_over_sections (info.abfd, |
| process_note_abi_tag_sections, |
| &os_ident); |
| |
| /* If that didn't help us, revert to some non-standard checks. */ |
| if (os_ident == ELFOSABI_NONE) |
| { |
| /* FreeBSD folks are naughty; they stored the string |
| "FreeBSD" in the padding of the e_ident field of the ELF |
| header. */ |
| if (strcmp (&elf_elfheader (info.abfd)->e_ident[8], "FreeBSD") == 0) |
| os_ident = ELFOSABI_FREEBSD; |
| } |
| } |
| else |
| os_ident = -1; |
| |
| for (arches = gdbarch_list_lookup_by_info (arches, &info); |
| arches != NULL; |
| arches = gdbarch_list_lookup_by_info (arches->next, &info)) |
| { |
| tdep = gdbarch_tdep (arches->gdbarch); |
| if (tdep && tdep->os_ident == os_ident) |
| return arches->gdbarch; |
| } |
| |
| /* Allocate space for the new architecture. */ |
| tdep = XMALLOC (struct gdbarch_tdep); |
| gdbarch = gdbarch_alloc (&info, tdep); |
| |
| tdep->os_ident = os_ident; |
| |
| /* FIXME: kettenis/2001-11-24: Although not all IA-32 processors |
| have the SSE registers, it's easier to set the default to 8. */ |
| tdep->num_xmm_regs = 8; |
| |
| set_gdbarch_use_generic_dummy_frames (gdbarch, 0); |
| |
| /* Call dummy code. */ |
| set_gdbarch_call_dummy_location (gdbarch, ON_STACK); |
| set_gdbarch_call_dummy_breakpoint_offset (gdbarch, 5); |
| set_gdbarch_call_dummy_breakpoint_offset_p (gdbarch, 1); |
| set_gdbarch_call_dummy_p (gdbarch, 1); |
| set_gdbarch_call_dummy_stack_adjust_p (gdbarch, 0); |
| |
| set_gdbarch_get_saved_register (gdbarch, generic_get_saved_register); |
| set_gdbarch_push_arguments (gdbarch, i386_push_arguments); |
| |
| set_gdbarch_pc_in_call_dummy (gdbarch, pc_in_call_dummy_on_stack); |
| |
| /* NOTE: tm-i386nw.h and tm-i386v4.h override this. */ |
| set_gdbarch_frame_chain_valid (gdbarch, file_frame_chain_valid); |
| |
| /* NOTE: tm-i386aix.h, tm-i386bsd.h, tm-i386os9k.h, tm-linux.h, |
| tm-ptx.h, tm-symmetry.h currently override this. Sigh. */ |
| set_gdbarch_num_regs (gdbarch, NUM_GREGS + NUM_FREGS + NUM_SSE_REGS); |
| |
| return gdbarch; |
| } |
| |
| /* Provide a prototype to silence -Wmissing-prototypes. */ |
| void _initialize_i386_tdep (void); |
| |
| void |
| _initialize_i386_tdep (void) |
| { |
| register_gdbarch_init (bfd_arch_i386, i386_gdbarch_init); |
| |
| /* Initialize the table saying where each register starts in the |
| register file. */ |
| { |
| int i, offset; |
| |
| offset = 0; |
| for (i = 0; i < MAX_NUM_REGS; i++) |
| { |
| i386_register_offset[i] = offset; |
| offset += i386_register_size[i]; |
| } |
| } |
| |
| tm_print_insn = gdb_print_insn_i386; |
| tm_print_insn_info.mach = bfd_lookup_arch (bfd_arch_i386, 0)->mach; |
| |
| /* Add the variable that controls the disassembly flavor. */ |
| { |
| struct cmd_list_element *new_cmd; |
| |
| new_cmd = add_set_enum_cmd ("disassembly-flavor", no_class, |
| valid_flavors, |
| &disassembly_flavor, |
| "\ |
| Set the disassembly flavor, the valid values are \"att\" and \"intel\", \ |
| and the default value is \"att\".", |
| &setlist); |
| add_show_from_set (new_cmd, &showlist); |
| } |
| } |